docs: def addSuffixToExtensions(toc):
      """
      Returns a new TOC with proper library suffix for EXTENSION items.
      """
      new_toc = TOC()
      for inm, fnm, typ in toc:
          if typ in ('EXTENSION', 'DEPENDENCY'):
              binext = os.path.splitext(fnm)[1]
              if not os.path.splitext(inm)[1] == binext:
                  inm = inm + binext
          new_toc.append((inm, fnm, typ))
      return new_toc